Here your circuit using diode OR's

That circuit will not work with real circuits unless there are pull-down resistors at the diode outputs.

I see no advantage to using the CD4017 over the simple circuit using a CD4013 FF I showed.

 

Hi Guys,
Interesting Topic, but please recall this is Homework.

Guidance only please.

Moderation

 

What did you do to the CD4017 model to make it work? Or did yours work straight away and there's something wrong with my 4017 model.

It worked fine straight away.

And you don't need the 4001s because the C and D waveforms are on the 0 and 2 pins of the 4017.

I've added labels to Q0 and Q2.
See graph below. The phase is shifted more than the TS wants.

 

That circuit will not work with real circuits unless there are pull-down resistors at the diode outputs.

I see no advantage to using the CD4017 over the simple circuit using a CD4013 FF I showed.

Agreed.